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The Economist.

From The Economist in London, this is Money Talks, a weekly conversation around themes in the worlds of

business, finance and economics. I'm Stan Penel, the banking editor. This year is shaping

up to be one of the slowest years for stock market listings of tech companies since the financial crisis.

That may seem odd at first given that every week seems to bring news of a new unicorn, Silicon

Valley slang for a private company valued more than $1 billion.

Some like Uber or Airbnb are now valued in the tens of billions with no IPO or initial

public offering in sight. Why are these seemingly successful companies taking longer to list?

Is something wrong with the public markets and can a billion dollar valuation and

private markets be compared to its equivalent on the stock market.

Alexander Sewich, our US technology editor usually in San Francisco, is with us in London today,

as is Ed McBride, our finance editor.

Alexander, let's start with you Square, which is a payments processing company, is breaking

ranks with a unicorn.

It's announced that it's listing.

...